Laboratoire de Chimie Organique, ESPCI ParisTech, UMR CNRS 7084, 10 rue Vauquelin, 75231 Paris Cedex 05, France.
J Org Chem. 2010 Aug 6;75(15):5151-63. doi: 10.1021/jo100871m.
Synthetic studies toward the spiroketal core of spirangien A are described. Two synthetic approaches were developed. Both of them use a diastereoselective aldol addition of a lithium enolate derived from a methyl ketone on an aldehyde. In the first approach, the introduction of the (E)-trisubstituted terminal olefin was achieved by using an iron-catalyzed cross-coupling between an alkyl iodide and a vinyl Grignard reagent and a randomly protected spiroketal was obtained. In the second approach, a highly functionalized spiroketal carbamate, which includes 13 stereogenic centers, was successfully isolated.
描述了对螺旋霉素 A 的螺缩酮核心的合成研究。开发了两种合成方法。它们都使用锂烯醇盐的非对映选择性 aldol 添加反应，该烯醇盐是由醛衍生的甲基酮形成的。在第一种方法中，通过使用铁催化的烷基碘化物和乙烯基格氏试剂之间的交叉偶联反应引入了（E）-三取代末端烯烃，并获得了随机保护的螺缩酮。在第二种方法中，成功分离出了一种高度官能化的螺缩酮氨基甲酸酯，其中包含 13 个手性中心。
